Taxis and shuttles provide the same basic service, but they are not the same thing.
A taxi driver will charge based on the amount of time it takes to get to your destination and takes passengers to a location of their choosing. Taxis are found around airports, big events and in large cities.
Riders typically "flag" or "hail" taxis down on the streets, or they can call a company to arrange a pickup time.
Most taxis will have a pickup fee and then charge per mile, per minute of waiting time and sometimes an additional passenger fee. Tips of 15 to 20 percent are standard.
If you opt for a taxi, make sure you choose one that's properly licensed. Most cities will offer a special license to taxi drivers who conform to regulations. Taxi drivers also undergo stringent FBI background checks.
A shuttle typically charges for the ride, with the driver only able to offer set destinations at set prices, such as from the airport to a popular hotel or city center.
Oftentimes, the service will run several times per day and will have very few if any stops between the starting point and destination.